Process of preparing haloid derivatives of acetone.



LEONHARD LEDERER, OF MUNICH, GERMANY.

PROCESS OF PREPARING HALOID DERIVATIVES OF ACETONE.

SPECIFICATION forming part of Letters Patent No. 643,144, dated February13, 1900.

Application filed August 10, 1897.

To all whom it may concern:

Be it known that I, LEONHARD LEDERER, a citizen of the Kingdom ofBavaria, residing at Munich, Bavaria, Germany, have invented a new anduseful Process of Preparing the Halogen Derivatives of Acetone, of whichthe following is a specification.

It is well known that the halogens act readily upon acetonedicarbonicacid. For instance, bromin added to an aqueous solution ofacetonedicarbonic acid is immediately taken up. An aqueous solution ofacetonedicarbonic acid decomposed with an alcoholic iodin solution takesup quickly the color of the latter without visible reaction. If,however, this mixture be gently warmed, reaction takes place, evolvingcarbonic acid gas; but the action of the iodld of hydrogen present inthe said iodin solution makes it difficult to obtain the products ofsuch reaction. To obviate this difficulty, I add to the mass a substancewhich has an aflinity for the iodid of hydrogen, thus removing itsdisturbing infiuence. this purpose. In this Way it is possible to usethe iodin to the utmost extent.

In carrying out my process I dissolve ten parts of acetone dicarbonicacid in ten times its mass of water and gradually add thereto twentyparts of iodin while the mixture is constantly stirred. The reactiontakes place promptly with a lively evolution of carbonic acid gas. It isadvisable to cool gently thereafter, because at a high temperature theperiodacetone is easily decomposed by precipitation of iodin. Theaddition of iodic acid must begin when the light-yellow mass takes on anorange color in reaction. As soon as the iodin is all used up thereaction is ended. The resulting periodacetone is then at once separatedfrom this liquid. Thoroughly washed and dried at ordinary temperature,it forms a light-yellow crystalline powder, which becomes dark onheating up to 60 centigrade. If it has previously been freed from water,it melts at 7 8 centigrade. On boiling with water it sets free iodin andbecomes pentaand eventually tetra Iodic acid serves excellently forSerial No. 647,759. (No specimens.)

The action of iodin on acetone-dicarbonic acid can be so regulated bydefinite diminutions of the quantity of iodin added as to result inlower stages of iodin combination with acetone. With regard to itsbehavior toward alcohol and ether the penta-iod derivative is in closerelation with the periodacetone. On the addition of dilute soda-lye itis trans formed into iodoform even in the cold, but not with the sodasolution. If one warms it with the latter, it is converted, as in thecase of tetra-iod-acetone, into di-iod-acetone. Bromin and chlorin actin a similar way with regard to acetone dicarbonic acid. In conse quenceof the liability of setting free halogen hydrogen acids it is notnecessary to take any special precautions in observing the progress ofthe reaction. In some cases it is advisable to add carbonate of calciumor similar substances to combine with the free acids or to use simplydilute solutions of the acetone dicarbonic acid.

The following is the equation for the use of ten molecules of bromin inthis process:

co. GH,

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

A process of preparing a halogen derivative of acetone by causing ahalogen to react with acetone dicarbonic acid in the presence of asubstance adapted to act on the corresponding halogen hydrogen acid,substantially as set forth.

LEONHARD LEDERER.

Witnesses:

CARL SINGER, PAUL MUNZ.

